From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0FC27C0650F for ; Mon, 5 Aug 2019 13:24:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D632520880 for ; Mon, 5 Aug 2019 13:24:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1565011496; bh=S0Xsl0T8+NAaR8iaxwLCK5CArJFaJjeMvLO7jaYnVA8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=hn+D0J/IlXnlfIW3k+gzGqk44ziV5AtVy518ulrF/uxtZE2Y+sbav6T9Y90d671lT AdH3Rzum6KHpJAPmHn17bDayORgOhIyIszreUn/Um4CAmkvehiOmONHZBpP09xtrAH 80nJYv782Zl5wAUzpzPqLzS0addioHFylLu1tF+Y= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731110AbfHENYz (ORCPT ); Mon, 5 Aug 2019 09:24:55 -0400 Received: from mail.kernel.org ([198.145.29.99]:33366 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731094AbfHENYw (ORCPT ); Mon, 5 Aug 2019 09:24:52 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 6E44420644; Mon, 5 Aug 2019 13:24:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1565011491; bh=S0Xsl0T8+NAaR8iaxwLCK5CArJFaJjeMvLO7jaYnVA8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=JlL9ZlXkybsQkAudLV1gOn/zz02Y6+h6QE/Ing4v6DTcIXktCb3sm2fWsjqkADeH/ h7ddvNKXjNx45eG9ZkDd2bPPN2bFXp4RDLs3edopfQe8koPWIUdGAKeWzkOAyNqVsv KPewA0llLGV8ge6aovc9g0Y1q5fzWgxUl6a/PSfI= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Jan Kara , Dan Williams Subject: [PATCH 5.2 081/131] dax: Fix missed wakeup in put_unlocked_entry() Date: Mon, 5 Aug 2019 15:02:48 +0200 Message-Id: <20190805124957.361969657@linuxfoundation.org> X-Mailer: git-send-email 2.22.0 In-Reply-To: <20190805124951.453337465@linuxfoundation.org> References: <20190805124951.453337465@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Jan Kara commit 61c30c98ef17e5a330d7bb8494b78b3d6dffe9b8 upstream. The condition checking whether put_unlocked_entry() needs to wake up following waiter got broken by commit 23c84eb78375 ("dax: Fix missed wakeup with PMD faults"). We need to wake the waiter whenever the passed entry is valid (i.e., non-NULL and not special conflict entry). This could lead to processes never being woken up when waiting for entry lock. Fix the condition. Cc: Link: http://lore.kernel.org/r/20190729120228.GC17833@quack2.suse.cz Fixes: 23c84eb78375 ("dax: Fix missed wakeup with PMD faults") Signed-off-by: Jan Kara Signed-off-by: Dan Williams Signed-off-by: Greg Kroah-Hartman --- fs/dax.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/fs/dax.c +++ b/fs/dax.c @@ -267,7 +267,7 @@ static void wait_entry_unlocked(struct x static void put_unlocked_entry(struct xa_state *xas, void *entry) { /* If we were the only waiter woken, wake the next one */ - if (entry && dax_is_conflict(entry)) + if (entry && !dax_is_conflict(entry)) dax_wake_entry(xas, entry, false); }